Manufacture of perforated metal for drainage-casings, screens, &amp;c.



AfsMHH, as orY PERKFQRVATED Mem FOR DRAINAGE CASINGS, SCREENS, m;

MANUFACTU -1Ai PLlcAT|0N FAILED 1u LY23.' I QMfMNEwED pic. 5, 1917.

n Pat @my V//XVM ww WAV/AMV@ I To 'alt whom t may conce-imi:

' MANUEAGTRE or r'EnroEATED METAL Eon DRAINAGE-memes, SCREENS, ac.

nennst.

Specification' of Letters Patent.

Application med imite-,1914, serial No. 852,654. 'Renewed remember 5.,1917. serial No. 205,685.

Be it. known that Ip, ANDREW SMITII, a citizen ofthe UnitedStates','residing at San Mateo, in the' county f of San Mateo andh'State of California, have invented certain new and useful Improvementsin the Manu- 'facture of Perforated Metal for Drainage- Casings,Screens, &c., of which the -followin'g lis a specification.

This'dnventicn relates to the manufacture ofv perforated metal `platesor sheetsl which are especially'adapted ffon use in making clasingsffor.drainage purposes, such' aswell curbing for lining-oil and water wells,til-j ing, culverts and also for screens and-,strainfill prefer toemploy a series of 'sets organgs of .tools which vfollow in succession,`each ers .in various arts, etc.

The main purpose' of my invention-iste provide perforated metal sheetsorplates l having smooth-walled slots or openings of any desiredwidth-.from the narrowestslit.

and to facilitate the manufacture of such plates. A furth'e'rlobject isto provide a process of manufacturing `slotted-plates in which theapertures .'may.v be cut bythe use of gangs of planing or milling toolsvor other cutting implements.v i 'p For the purpose of clearly:Adisclosing this invention reference is made to the accompany-ing drawingin'which-Figure 1 is a cross-section'showingthe edge or thickness of ametal 'sheet Fig. 2' is the same after being corrugated; Fig. 3 is a Aperspective view of the corrugated plate; `shoviving the manner ofcuttingtheslotsby means of successive gangs of tools; llig. 4 isalongitudinal section of the 'slotted-J plate after the A corrugationshavev been pressedback into theplane of the sheet; Figs. 5' and 6,v arev,smooth casing is desired, the slotted-plate transverse sectional views'of'v slotted plates showing different shapes of slots andthecorresponding cutting tools; and Fig. 7 .is a

sectionalV` view of a perforated plate bent into semi-circular shape toshow the manner offormingl drainage casings.

The first step inthe process of s lotting vnally of the plateucan passentirely `through rows .in the manner indicated in Fig. 3, by.'gajngs'of cutting tools 6, which move. over `the sheetin a planeparallell therewith. The

essere@ I ANDREW SMITH, 0E SAN MATEO, CALIFORNIA Patentes muy e, Isis.

slots are cut in successive stages7 which may to cut deeper atsuccessive movements,but

succeeding gang cutting deeper into the 'bedone by adjusting the 'gang.of cutters metalV 'than'the preceding gang a-nfd being coperate` informing the'desired crosssecof the sheet, the gangs of tools 6 will beofthe shape as shown in Fig. 6, and merely dierin the depth of cut.

Drainage casings, such `as well curbing,`

culverts,tiling, etc., 'may lbe formed from sheets perforated withslots, as shown in Fig. by .bending the sheets into .tubular or pipeform, the upper side in said figure forming 'the inner side of thecasing` and the corrugations 2, j constituting convex bands" encirclingthe-pipe. lf, however, a

lshown in Fig. 3', is subjected to a pressing 'or rolling, operation toforce the corrugain cross section in Fig. 5. If the sheets formed inthis manner are bent into tubular form in the `manufacture of drainagecasings with the upper side in said illustrations constituting theinside of the casing,

the'vslotswill be' narrowest at the outside,

becoming wider in passing through the wall of 'the casing as shown inFig. 7. The advantage cf V-shaped slots lies inthe fact ..that anyparticles which can pass through the slots from the narrow outsideopening 'also preferably so shaped. as to'progressively Vtional shape'.`When the slots are to be -V- tions 2 -back into the plane of the'sheet, as

shown in longitudinal section in Fig 4, and

will immediately ass into an evervide'ning channel thereby e iminatingany danger of clogging the slots; A

Having fnow 'described the process "of forming slottedv plates o rsheets according to my invention and having pointed out some of the usesof resulting product, I claim 1. The process of making perforated metalsheets or plates for strainers, drainage cassheets or platesfor'strainers', drainage cas'- ings, etc.,'con 1prising forming a seriesof eor'rugations 1nv the metal plate, to raise portions "of, the metalabove the plane of the intervening portions, and cutting a series ofparallel slots through they` raised portions transversely of thecorrugations.

3. The process ofmaking perforated metal sheets, or plates forstrainers,drainage cas.- ings, etc., comprising forming a ser-ies of corrugationsin the metal plate, to raise/'portions of the metal above the plane ofthe intervening portions, said raised portions being flattenedsubstantially throughout their extent, and cutting a series of parallelslots through the raised portions -transverselyr of the .corrugationsvIntestimony whereof-'I ailix my signature in presence of two Witnesses.

lANDREW SMITH.

Witnesses:

E. C.' BROWN, K. HARTIG.

